Download unit one: turtles of ontario

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UNIT ONE: TURTLES OF ONTARIO
Science Expectations met in this unit:
Activity Number:
Activity Name
1: Turtle Trading Cards
2: Turtle Identification
3: One of These Things
Is Not Like The Other
4: Guess Who?
Strand
Specific Expectations
Understanding
Basic Concepts
Grade 1 – Characteristics
and Needs of Living
Things
Grade 2 – Growth and
Changes in Animals
Grade 6 – Diversity of
Living Things
Grade 6 – Diversity of
Living Things
Grade 7 – Interactions
Within Ecosystems
Grade 2 – Growth and
Changes in Animals
Grade 6 – Diversity of
Living Things
Grade 2 – Growth and
Changes in Animals
Grade 6 – Diversity of
Living Things
Grade 7 – Interactions
Within Ecosystems
Developing Skills
of Inquiry,
Design and
Communication
Relating
Science and
Technology to
the World
Outside the
School
1, 3, 4
1, 4
3,5
5
3, 5
5
5
1, 3, 4, 8
11
2
1,3 5
1,3
3, 4, 5
1, 3
3, 4, 5
1, 3
3, 5
3
3, 5
2
1, 3, 5
3, 5
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SECTION ONE:
Turtles of Ontario Fact Sheets
BLANDING’S TURTLE
Scientific Name:
Class:
Order:
Family:
Genus:
Species:
Emys (Emydoidea) blandingii
Reptilia
Testudines
Emydidae
Emys (Emydoidea)
blandingii
Emys (Emydoidea)
blandingi
emydos = freshwater turtle
oidea = like
blandingi = Dr. W.
Blanding who collected
this turtle for its original
description
Description
• Adults are usually between 12.5-18 cm in carapace length;
• Smooth, domed, black to greyish-brown carapace with numerous yellow
streaks or spots that become obscured in older turtles;
• Plastron is either almost completely black or yellow with a dark, large
blotch in the corner of each scute;
• The plastron is hinged to protect the head of the turtle when recoiled;
• The chin and throat are bright yellow;
• Eyes are protruding.
Feeding
• Omnivorous;
• Feed on crayfish, insects, fish, frogs and plants.
Breeding
• Females mature after 14 years;
• Nests are dug in sandy areas between late May to July and have
been observed in soil, on muskrat huts, roadsides and gravel sites;
• Females lay a single clutch of 6-11 oval, dull white, hard-shelled eggs;
• Hatchlings emerge in the fall and are 3-4 cm in length;
• The temperature of the egg in the nest determines gender of hatchling.
Habitat
Blanding’s turtles live in soft-bottomed, highly productive waters with dense aquatic vegetation.
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Distribution
• Ontario:
• Canada: Isolated populations in southern Ontario, western Quebec and Nova Scotia;
• USA: Limited to the Great Lakes region with some populations along the Atlantic Coast
and west to Nebraska.
Interesting Facts and Behaviour
• Bask on muskrat houses, logs, driftwood and stumps. Occasionally bask on land;
• Pattern on the carapace imitates duckweed and provides great camouflage at the
surface of the water;
• Can live up to 25 years and some reports state that it could live up to 70 years!
• Hibernate under water in mud and may even be found at entrances to muskrat houses.
Status
The Blanding’s turtle (Ontario population) is not designated at risk provincially in Ontario or by
COSEWIC. The Blanding’s turtle (Nova Scotia population) was designated threatened by
COSEWIC in 1993.
Conservation Concerns
• Will abandon basking sites and nests if disturbed;
• Traffic mortalities;
• High nest predation;
• Loss of wetland habitat.
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NORTHERN MAP TURTLE
Scientific Name:
Class:
Order:
Family:
Genus:
Species:
Subspecies:
Graptemys geographica geographica
Reptilia
Testudines
Emydidae
Graptemys
geographica
geographica
Graptemys geographica
geographica
graptos = inscribed or
painted
emydos = fresh-water
tortoise
geo = earth
graphe = line drawing
Description
• Smaller males range from 9-15.9 cm and females range from 18-27.3 cm in carapace
length;
• The carapace is oval with a serrated back edge and a slightly raised keel;
• The carapace is brown with fine yellow lines running down its surface (resembling a
map), which may be faded in older turtles;
• The plastron is yellow in colour;
• Head and limbs have light yellow and dark stripes;
• Yellow spot, variable in size, behind each eye.
Feeding
• Males feed from May through to August or September. Breeding females begin feeding
after eggs are laid (usually July);
• The preferred food source is molluscs. Insects, fish carrion and plant material are also
eaten.
Breeding
• Females require 10 years to reach maturity;
• Breeding occurs in late fall or early spring near hibernacula;
• Females dig nests from May to July;
• In Ontario, one clutch of up to 17 eggs is laid. Eggs are laid within 100 m of the
shoreline;
• Hatching occurs 60-75 days after eggs are laid. The temperature of the egg within the
nest determines the gender of a hatchling.
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Habitat
Map turtles inhabit larger rivers and lakes with slow moving, high quality water (an ideal
environment for their primary food source, molluscs) and a soft bottom.
Distribution
• Ontario:
• Canada: Widespread in Great Lakes/St. Lawrence watershed from southern Ontario
into Quebec;
• USA: Found in northwest Vermont west to the Mississippi drainage of Minnesota and
south to Arkansas and northern Alabama.
Interesting Facts and Behaviour
• Home range size is greater for females (up to 70 ha) than males (up to 30 ha) and
includes areas for hibernating, basking, nesting and feeding;
• At night, adults rest on submerged logs in deep water to avoid predators;
• Adults hibernate communally in the deepest water available;
• Known for their communal basking, many individuals may be found piled up together on
partially submerged logs, branches or rocks near deep water. Basking is important for
the successful development of the eggs in pregnant females;
• Predators include foxes, racoons and otters, ring-billed gulls, crows, mink, coyote,
grackles and red-winged blackbirds. In rare cases, grackles have been seen removing
the leeches from adult turtles.
Status
The northern map turtle is not designated at risk provincially in Ontario. It was designated a
species of special concern by COSEWIC in 2002.
Conservation Concerns
• Vulnerable to shoreline development, which destroys nesting habitat, and to water
pollution due to the turtle’s dependence on molluscs as a food source;
• Adult females are susceptible to traffic mortalities as they wander in search of potential
nesting sites;
• Loss of the aquatic corridors the species requires for movement.
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COMMON MUSK TURTLE
(a.k.a. STINKPOT)
Scientific Name:
Class:
Order:
Family:
Genus:
Species:
Sternotherus odoratus
Reptilia
Testudines
Kinosternidae
Sternotherus
odoratus
Sternotherus odoratus
sternon = chest or breast
thairus = hinge (in
reference to hinge across
plastron)
odorus = fragrant (in
reference to the musky
smell when handled)
Description
• Musk turtles are usually between 5.1-11.5 cm in carapace length;
• Dome-shaped, smooth carapace that is light olive to black in colour;
• Plastron is small, yellow-brown with a single hinge. The front part of the plastron
has limited movement and allows only partial protection;
• Each side of the head has single yellow stripes above and below the eye;
• Chin and throat are covered with barbels.
Feeding
• Omnivorous, often scavenging for food;
• Bottom feeders whose diet consists of algae, carrion, small
invertebrates, fish eggs, minnows and tadpoles.
Breeding
• Adults mature between 3-7 years of age;
• Breeding occurs year-round, but mainly in the spring; females are able to store
sperm if mating occurs in the fall;
• Nesting occurs from May to July. The nests are very shallow, and sometimes
exposed;
• The female lays a single clutch of 2-5 hard-shelled, white, oval eggs;
• Hatchlings emerge in the fall and are usually 2 cm in length;
• The temperature of the egg within the nest determines a hatchling’s gender.
Habitat
The common musk turtle prefers to live in the shallow areas of soft-bottomed, slow moving
water such as rivers, lakes and ponds. It is rarely seen on land or basking.
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Distribution
• Ontario:
• Canada: Southern Ontario, and at some locations in Quebec near the Ottawa River;
• USA: Southern Maine south through peninsular Florida, west to central Texas and
northern Wisconsin.
Interesting Facts and Behaviour
• Also referred to as the ‘Stinkpot’ because of the musky odour it produces when it is
handled;
• Nocturnal but may be active throughout other parts of the day;
• Rarely leaves the water and therefore rarely seen basking. Usually covered in a thin layer
of algae;
• May climb trees or branches overhanging the water;
• Very aggressive when handled;
• Hibernate in muddy sediments during the winter;
• Ontario’s smallest turtle.
Status
The common musk turtle is not designated at risk provincially in Ontario. It was designated as a
threatened species by COSEWIC in 2002.
Conservation Concerns
• Occasionally caught by anglers using minnows or worms on hooks;
• Habitat loss and fragmentation.
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COMMON SNAPPING TURTLE
Scientific Name:
Class:
Order:
Family:
Genus:
Species:
Subspecies:
Chelydra serpentina serpentina
Reptilia
Testudines
Chelydridae
Chelydra
serpentina
serpentina (Common)
Chelydra serpentina
serpentina
Chelydros = a mythological
water serpent
chelon = a tortoise
serpentis = serpent
Description
• Largest freshwater turtle in Canada. Adults are usually 20.3-36 cm in carapace length
and weigh between 4.5-16 kg. Some individuals can reach sizes in excess of 47cm in
shell length. Largest ever recorded lived in Toronto Zoo and weighed 32 kg;
• Carapace can be light brown to black in colour;
• Young turtles have three longitudinal keels (raised ridges) while older turtles may be
smooth;
• The plastron is yellowish, very small and cross-shaped. It does not offer much protection
for the turtle’s underbelly;
• Head has two barbels on chin, and the neck is covered with rounded tubercles;
• Serrated tail is crocodilian in appearance and is the same length as or longer than the
carapace.
Feeding
• Omnivorous, often scavenging for food;
• Main staples are fish, invertebrates and plants, but diet can include salamanders, toads,
frogs, tadpoles, small turtles, snakes, young waterfowl, small mammals and carrion;
• Sharp beak and strong jaws.
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Breeding
• In Ontario, females do not breed until they are 17-19 years old, but it is size, more than
age, that determines when a female is capable of breeding;
• Females build nests in May or June in gravel, sand, soil or mulch. Turtles seen on land or
crossing roads at this time of year are usually females searching for egg-laying sites;
• Females lay a single clutch of between 20-40 eggs. The eggs resemble ping-pong balls;
• Eggs hatch in the fall and hatchlings are 2-3 cm in length. They immediately hide under
the leaf litter and/or move towards water;
• Eggs may not hatch at all if fall temperatures are cold;
• The temperature of the egg within the nest determines the gender of a hatchling.
Habitat
The common snapping turtle prefers slow-moving water with a soft bottom and plenty of
vegetation. It is found in many freshwater habitats, especially shallow ponds, rivers, streams,
canals and lakes.
Distribution
• Ontario:
• Canada: Occur from the Maritimes west into southern Saskatchewan and parts of
southern Alberta. New Brunswick populations are isolated.
• USA: It is found in all areas of the United States east of the Rocky Mountains.
Interesting Facts and Behaviour
• Snapping turtles rarely leave the water. They swim away from danger or people when in
the water;
• On land, the common snapping turtle is vulnerable due to its small lower shell and
therefore may become aggressive;
• Hibernate in the muddy bottom of a wetland, under logs or under overhanging banks of
ponds, streams or lakes;
•
•
•
Can release a foul-smelling liquid from glands under the carapace;
World’s largest common snapping turtle (32 kg) was once a resident of the Toronto Zoo;
Ontario’s largest turtle.
Status
The common snapping turtle is not designated as a species at risk provincially in Ontario or by
COSEWIC.
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Conservation Concerns
• Traffic mortalities as females search for nest sites;
• In some areas the common snapping turtle is considered a food delicacy. Many
populations are impacted by over-trapping;
• Often persecuted due to misinformation on its perceived threat to game fish and ducks,
as well as to people (especially swimmers). It does not bite swimmers.
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